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The Speakers With The Deepest Bass: Tactile Transducers -- Reactual. In A Nutshell The speakers that produce the lowest bass are tactile transducers — they typically produce frequencies in the 0.5 – 20 Hz range. Tactile sound is not perceived through the ears — it perceived through the body. Most subwoofers are incapable of producing audio in this range.

A good tactile transducer to start with is $150, entry-level Clark Synthesis Silver Edition (TST239) — it provides ample sub-frequency bass for the home user. The Details Tactile sound is the sensation of sound transmitted directly to the human body by contact, rather than by sound waves through the ears (tympanic sensation). More specifically, it is sound perceived through bone conduction, through muscles and deep tissue, and via skin sensation. Tactile sound can be perceived in high fidelity up to the mid-range frequencies. Tactile sound is a sensation that many seek out. So what kind of device produces tactile sound? There are two basic flavors of transducer: inertial shakers and linear actuators. What are the techniques engineers use to get deep bass out of a speaker driver? - Quora. How to Make Your Own Speakers Easily. Designed by Megan Tatem Advertisement - Continue Reading Below It was back in 1924 that a couple of researchers from General Electric, Chester Rice and Edward Kellogg, patented what remains the basic design for virtually all the world's loudspeakers.

In the 84 years since, engineers and enthusiasts have invested a lot of thought and energy in the refinement of Rice and Kellogg's concept, creating a valuable knowledge base for the do-it-yourself crowd. I should know--I recently built the speakers pictured here, and in the process I learned quite a bit about the art and science of a good speaker. At its core a loudspeaker is a surprisingly simple device At its core a loudspeaker is a surprisingly simple device. Hardcore speaker hobbyists take delight in figuring all this out for themselves, designing and building the crossovers and enclosures from scratch to see what comes out. The kit costs $369 for the pair and comes with everything except lumber and wood glue Gluing and clamping the fascia. B&O Tech: How to Make a Loudspeaker Driver (A primer) – earfluff and eyecandy. #11 in a series of articles about the technology behind Bang & Olufsen loudspeakers I realised this week that I’ve been throwing around words like ” voice coil”, “suspension”, “surround” and “spider” when I talk about loudspeakers, but many people don’t know what these things are – or how a loudspeaker driver works in general… So, this week, I thought I might back up a couple of steps and talk about some basics.

There’s nothing here about Bang & Olufsen loudspeakers specifically – it’s just an introduction to how loudspeaker drivers (like woofers, for example) work. Back in 1820, a Danish guy named Hans Christian Ørsted was in the middle of giving a lecture when he noticed that, when he switched a circuit on and off, a compass sitting nearby on the desk moved a little. Nowadays, we know that, by putting current through a wire, you produce a magnetic field that has magnetic lines of force that encircle the wire. So, let’s do something weird. One little extra piece of information here. Acoustic imaging with outline detection. Reverberated sound can make objects visible. The sonar is used in the shipping industry to acquire information about the seabed or shoals of fish, while gynaecologists use ultrasound images to study foetuses in the womb.

Material testing procedures that regularly check for fissures in rail tracks or aircraft support structures are also based on ultrasound. Researchers at ETH Zurich have now developed a new type of acoustic imaging device which, rather than producing a photorealistic image of an entire object, shows only its contours and edges. “This type of measuring method delivers similar results to the edge detection filter in an image-processing software, which allows the outline of prominent photo objects to be identified with the click of the mouse,” explains Chiara Daraio, Professor of Mechanics and Materials.

Her method, however, is not software-based. Robert White, Tufts University. Liquid Metal Interconnects for Conformable Sensor Packaging Enabling Inertial Measurements of Animals and Soft Robots Nikolas Kastor1 and Robert D. White2 1 Tufts Mechanical Engineering Graduate Student 2 Tufts Mechanical Engineering Faculty In biomechanics, inertial measurements units (IMUs) are used to map the dynamic modes and gates of locomotion of animals. Typically, thin wires are soldered to the IMU and the package is bonded to the location of interest, on the animal, using cyanoacrylate or epoxy. Fig: A soft PDMS encapsulated sensor system with embedded inertial measurement system IC, discrete components, and microfluidic channels for liquid-metal interconnects.

Relevant Publications: Nikolas Kastor and Robert D. MEMS Surface Shear Sensors for Aerodynamic Applications Zhengxin Zhao2, Nikolas Kastor2 , Daniela Torres1, and Robert D. 1 Tufts Mechanical Engineering Undergraduate 2 Tufts Mechanical Engineering Graduate Student 3 Tufts Mechanical Engineering Faculty Zhao, Z. Liu, S. Microphone arrays to unlock the potential of speech recognition | XMOS.

Dag Kittlaus, CEO of Viv Labs (, has recently given some impressive demonstrations of his latest AI technologies, but one thing that always looks odd during the Viv demonstrations is that he holds the phone very close to his mouth. He’s almost eating his phone every time – it’s like something from Trigger Happy TV. Dag needs to make sure that the quality of captured speech is clear enough for the software to decipher the content of the commands, but it’s not a real-world scenario.

We’re not all going to want to "eat" our phones in order to book an airfare for next week. Voice interfaces are sometimes called conversational interfaces for good reason - they allow users to talk to the device instead of using touch screens and buttons to execute a command. Conversations take place between two or more people who may be next to each other but are often a couple or more meters apart.

Microphone arrays How complex are microphone arrays? Why do you need acoustic DSP? Putting it all together. Ultrasonicmobile. Ultrasonicmobile is a performance system comprised of three functions: capturing ultrasonic information in the sonic environment using a MEMS microphone array designed by Ivano Pelicella of Dodotronictransposing the captured ultrasound in realtime to human hearing range using a customized Raspberry Pi micro-controller system designed by Hector Centeno broadcasting that transposed signal back into the environment using a directional speaker called the Audio Spotlight Performances with the system can take the form of a soundwalk where the audience goes on a walk for the purpose of not only listening to the sounds of the environment, but with the intervention of the ultrasonicmobile, to hear the ultrasonic layer that normally is inaudible.

Common household objects such as house keys or video display screens contain ultrasonic information that our bodies absorb physically but that our brains do not process as auditory information. Media Credits Ultrasonicmobile Recording System. LOUD: Large acOUstic Data Array Project. A 1020-Node microphone array and beamformer at the MIT Computer Science and Artificial Intelligence Laboratory. Data Please see the data page for experimental data collected with the array.

Purpose Ubiquitous computing environments are characterized by an unbounded amount of noise and crosstalk. In these environments, traditional methods of sound capture are insufficient, and array microphones are needed in order to obtain a clean recording of desired speech. The LOUD (Large Acoustic Data Array) is a novel 1020-node microphone array utilizing the Raw tiled-processor architecture (TPA) for computation.

The LOUD modular microphone array currently consists of 1020 microphones. People Prof. Publications E. Pictures Pictures here Videos Microphone Array and Stereo Camera integration -- tracking two people as they move around. Computer Architecture Group ecoder at-sign alum period mit period edu.